Apparatus for re-refining lubricating oil



April 29, 1947- MJ. LIVINGSTON 2,419,579

APPARATUS FOR RE-REFINING LUBRICATING OIL Filed Aug. 4, 1944 5 sheets-sheet 1 f April 29, 1947- M. J. LIVINGSTON v 2,419,579

APPARATUS FOR RE-REFINING LUBRICATING OIL Filed Aug. 4, 1944 3 Sheets-Sheet 2 Patented Apr. 29., 1947 vUNITED STATES l PATENT '0F FICE APPARATUS FOR RE-REF-INING LUBRIGATING OIL v-Myran J.'Livingston,Pelham, N. Y.

.Application `August 4, 1944, Serial No. 548,114

1 This Yinvention relates to 'aprocess `andallparatus for contact filtration of Voil, :particularly for th'e purification of lubricating oil. My process and apparatus find a .particularly useful application .to the -re-reiining of used llubricating oil of petroleum origin. .Such used oil may constitute the steam .engine lubricants, vdrairlings from crank cases of gasoline, gas, or Diesel engines, used turbine oils, .and engine and other lubricating oils used in lubrication of machinery. It is now Well established that lubricating oil which has deteriorated in use to such an extent that its replacement by .rened oil is economically advantageous may be, if properly .re-refined, placed in a condition such as to make it again .useful as a lubricating oil. In fact, I have found when suchan oil is re-refined according to my process and when employing .my apparatus not only does the oil have as good .properties as th'e original oil when subjected to all the conventional tests, but in many of its properties, vparticularly in its resistance to oxidation, it is vimproved in quality.

This improvement in lubricating oil properties I believe to .be the result of `deep-seated and vimportant changes in the -chemical constitution of the oil resulting from a controlled oxidation of the used oil in the presence of an active adsorbent and catalyst. Used lubricating oil, es-

pecially oil drained from the crank cases and sumps of internal combustion engines, such as the gasoline engine, gas engine, and Diesel r semi- Diesel engines, here included under the term used lubricating oil, has been subjected to relatively high' temperatures under oxidizing conditions. Such oils contain, in addition to sludge, partially oxidized and partially vpo'lyrnerized compounds which are themselves reactive, and on continued use will oxidize, polymerize, and resinify. These materials also have `a catalytic effect in that they promote the resin-ication and oxidation of the oil. The process, asis wellknown, is auto-catalytic. Thefexact composition of these oxidized fractions which impart this .instability and auto-catalysis is not known to petroleum scientists, but the latest theory supported by .the most facts is th'at they are organic peroxides formed by the oxidation of oil. vThe ,process of controlled pre-oxidationin the presence of a catalytic adsorbent causes an 'oxidation of the `unstable and catalytic .components of the oil .fraction and their .immediate .removal ,from the zone ofvoxidation'by adsorption .on the solid adsorbent. The peroxides and other intermediate compounds forming .Dart of the chain reaction of oxidation 5 Claims. (Cl. 19H-16) are removed'from the oil by adsorption. v By this process of adsorption, the unstable and `unstabilizingcomponents are removed byadsorption or oxidized and removed by adsorption, thus preventing the re-accumulationofperoxides or other catalytic materials in the oil which thereafter,

on continued use, Yagain unstabilize the oil.

lParallel to this process stabilization of the oil by pre-oxidation in the presence of catalytic adsorbent, the adsorbent also exhibits its normal adsorptive capacities to remove color bodies, sludge, carbon, moisture, .unsaturated and unstable vbodiesnot converted by the oxidation process.

The purified oil after subjection to blowing with air atelevated temperatures in the presence Yof solid vadsorbent having catalytic properties, herein referred to as the pre-oxidation process,'is then cooled Ain :an vinert Vatmosphere until .it .is below an active oxidation temperature and then .separated -from the-adsorbent.

I Abelieve this .step to be important, in that oxidation, in the absence of an adsorbent which wouldllave theproperty of removing the products of oxidation, would leave in the oil peroxides, acids, .and other oxidation catalysts to unstabilize the oil. By cooling the clay and oil mixture to belowan.active-oxidationtemperature and permitting a partial separation of the clay, I may then use air pressure fas va convenient means of pressure filtration without incurring the danger of unstabilization by'oxidation.

While my process is applicable to and may be employed in many forms of apparatus, the apparatus hereinafter -described is 'in such simple and 'convenient form as 'to make my process available and economical for use in garages, oil service stations, yand even for operators of but a small number-'of cars,`buses, or automobiles.

lSuch a need 'has been long 'felt but no apparatus vsufficiently economical to make it available to the small operator is available. "This device, therefore, it is believed, iills a long-felt and longunsatised need.

In principle, my apparatus provides a simple mechanism for v.flowing air through 'the heated oil to which 'the adsorbent has .been added. The air causes a pre-oxidation of the oil as described above. It .also has the advantage of keeping the oil and .adsorbent Well mixed during the treatment.k This 4.avoids moving parts vto agitate the The uncondensed vapors from both stages, i. e.,;'

steaming and air blowing, are disposed of by intermingling with Water in the Waterv jet which,

maintains a suction of the condenser and treater'.

The oil and adsorbent are then transferred from the contactor into a cooling chamber byvr steam pressure in the absencey of air and cooled while out of contact with air. lIt will be seenv that all machinery for transferring, agitating, and filtering the oil is made by steam or air pressure. The adsorbent is thenrremoved from the cooled oil by filtration, using air pressure.

This invention will be further described by ref;Y erence to the accompanying drawings which illustrate a preferred embodimentof myinvention. In the drawings:

Fig. 1 is an assembly view of my apparatus taken in part vertical section along the line I-I of Fig. 2;

Fig. 2 is a plan view shown in part section taken along the line 2-2 of Fig. 1; y

Fig. 3 is another section taken 90 to the sec tion of Fig. 1 in the direction of arrow 3 on Fig, 1;

Fig. 4 is a detail of the heater employed inthe contactor-reactor;

Fig. 5 is a fragmentary detail of the filter; Fig. 6 is a fragmentary detail of the bottom of the filter of Fig. 5;

Fig. 7 is a diagrammatic flow sheet illustrating the apparatus and its use; and

Fig. 8 is a cross section of a suitable container for the treating agent for use in a modication of my invention. v

The treating chamber I is preferably formed of a flat-bottomed and flat-topped cylindrical vessel. The choice of such avessel permits of an economical construction for a cost far less than would be entailed in employing vessels with bumped heads'and cone bottoms. In order, however, to obtain the benefits of a cone bottom, permitting a complete transference of material and also efficient agitation and mixing of oil and adsorbent, I have employed the expedient of mounting this treating vessel so that its axis is inclined, for example, at approximately 45 to a horizontal plane, as will be described below. Vessel I, hereinafter referred to as a contactor, is formed with a bottom 2 set at some short distance from the end of the Wall of the vessel I to give acylindrical flange 8 to house the electrical resistor heater I to be described below. A spout 4, whose axis is s et about 45 to the axis of treater I, carries acap accessible from the exterior of the enclosing cabinet I9. The contactor I is surrounded by insulation 46 and enclosed with a metal housing 1.

The electrical heater I0, referred to above, shown in Fig. 4, is mounted underneath the bottom 2 by means of clips and bolts II. Such resistorsare well known and may be purchased in the open market. They are particularly useful foruse in my type of apparatus and are superior for my purpose to immersion type of heaters, since they avoid the necessity of providing fittings which will pass through the walls of the treater.

4 They are also lower in price than the immersion type heater. An additional advantage is the simplicity of installation and removal. The insulation may be made sectional to t over the fittings of the vessel. A bottom portion may also be provided suitably attached to the enclosing metal Wall 'I. By removing the bottom portion, the heateris. accessible and may be installed or removed. .l L i Passing through the walls l and I is a thervmometer Well I2, closed at the bottom, to provide a, means for measuring the temperature of the oiljin contactor I. A thermostat I3 is passed through the walls of 'l and I and securely .mounted in anairtight and leak-tight tting.

As illustrated in Figs. l, 2, and 3 the contactor I is mounted in its inclined position by means of clips: Irland I5 positioned on angles I6, I1, and I8 mounted on the walls of the enclosing cabinet I9. This cabinet surrounds the entire apparatus and gives'a neat appearance to the device.

team generator 2i! carried bythe top of the housing I9 is covered by a closure 2i carrying a clamp tting 22. Closure 2i Amay be held by clamp 22 by means of a spring so that it may act as a pop valveto become unseated and relieve pressure if the steamy pressure in 2li becomes excessive. The closure is accessible from the top of the cabinet as illustrated in Fig. l. Beneath the bottom of the steam generator 20 is positioned a resistor heater 23 s imilarin character to IU. A pipe 2li is connected near the top of generator 2li and passes through the walls 1 and i to connect with@ pipe 25 lying on the bottom ofthe contactorv I.V Pipe 25 terminates near the lowest portion of contactor I, as is shown in Fig, l. It may be in the form of a spider, permitting discharge of air orsteam'at various points across the bottom 2, as well as the lowest point in the contactor I. This will assist in thorough agitation and oxidation and purging by improving the contact of air or steam With all portions of the oil and treating agent. A pipe 2l is connected near or at the uppermost point of the inclined contactor I. A pipe 28 passing through the wall "I and the top 3 ofthe contactor I terminates in the lower point of the inclined contactor. A drain line 9 closed by a capis mounted at this point, as shown in Fig. 1.

Thisconstruction permits of the discharge of the contents of the contactor I through line 28, as will be explained hereinafter, and through drain line 9 in the same manner as ifv the contactorvhad been positioned vertically and a more expensive cone bottom provided. This expedient permits of a material saving in the cost of construction of the apparatus.

The pipe 2l communicates with a condenser 3i) through valve 29. As shown in Figs. 2 and 3, the valve stem of valve 2 9 is elongated and the4 wheel ZSjof the valve ismounted above .the top of the housing iii` and `is accessible at that point.l

The condensate accumulator 3D is covered by, a top 3| heIdseCurelyWith a gas-tight closureby means of albolt 32 screwed into a bracket 33. A valved spout 34 is connected to the bottom of the accumulator 3,0 and passesthrough the wall of the housing I 9.

This accumulator carries a condenser coil to which water for cooling purposes is passed through pipe dcontrolled by valve 35. .The valve stem and wheel 3 5.' is accessible fromthe top, of cabinet I9, as shown'in Figs. l, 2, and 3. The cooling. Water A.from the condenser coil discharges through pipe '36 which is in turn connected to the cooling coil i4 in cooler 4|. A vent pipe 3l is connected to the upper portion of the accumulator and this vent line carries a sight-glass 38 and also a valve 30, whose valve stern and wheel 39 are accessible from the exterior of housing I9. A cross fwd, which carries a pressure gauge 40', is mounted exterior oi'the ho-using it! and is connected by line 60h to the upper portion of the cooler 4|, as will be described later. Pipe 3l also carries a check valve 4Q. Connected to the upper portion of theaccurnulator 30' is a pipe 48 which is connected to the ejector |15. The ejector is connected to the coil Il in the cooler lll. The discharge from i'e enters spout il which, ii desired, may be connected to 46 by a gas-tight fitting. The spout @l may be connected to the sewer,

The cooler 4l isvformed of a cylindrical Vessel with a flat top and iiat bottom. .it is mounted at an angle, for example, a angle, on clips 52" and 55" on brackets 53 and 52 positioned on the walls of the housing I9. As described in connection with contacter i, this expedient gives to the flat-bottomed vessel 4| the advantages of a cone bottom. To the upper portion of the container 4| is connected pipe 42 which is in turn connected through valve 43 with the pipe 28 previously described. The valve 43 has a valve stem 43 projecting from the top of the housing l@ and is accessible at that point. To the lowest portion of 4| in its inclined position is connected a pipe 49 which in turn is connected to the housing of the lter 5l through valve 50. The bottom of the filter shell 5I is closed by a perforated closure 54 which carries a screen 53 and a lter 52. This lter may be lter paper, filter cloth, blotting paper, canvas, or other type of filter diaphragms. The lter is preferably some paper such as blotting paper-which can act as a gasket to seal the closure at the wall of the shell 5 l. The perforated closure 5t is held tightly against the shell 5| by means of a swinging clamp 55 and a bolt 56.

The apparatus previously discussed is schematically illustrated in Fig. '7, which also shows the wiring diagram for the unit. A power line 5l is connected to the heater 23 through a switch 59. The heater l0 is connected to line 5l through switch 58 in series with the thermostat I3 and light 64. When the temperature is below the predetermined upper limit at which the therrnostat is set to open the current, the light is on` When the temperature rises above the safe upper limit, the thermostat breaks the circuit and the light goes out. A visual warning is thus available.

The operation of this device and the application of my process for the re-refining of used lubrieating oil are illustrated by the diagrammatic ow sheet of Fig. '7 taken together with the description of the apparatus previously given.

The cap 2| is removed. Water is introduced into the container 20 to a level below the outlet pipe 24. The cap 5 is removed and valve 5!) is closed. The used'oil to be re-rened is poured into the contactor to leave a vapor space above the level of the oilf The treating agent is then introduced through the spout 4.

The treating agent may be any useful type of adsorbent such as an adsorbent synthetic magnesium silicate, natural decolorizing clays, such as natural magnesium silicate clays, acid treated montmorillonite clay, such as the acid activated bentonite clays, Activated Alumina, or activated adsorbent carbon. I prefer, however, to employ adsorbents which are also catalytically active in promoting the treatment hereinafter described. Acid treated sub-bentonites are well known catac from crude oils.

CII

6 lysts for the cracking of oil and have been employed as decolorizing and purifying adsorbents in the rening of lubricating oils as produced They have been employed in refining used lubricating oils. They are particularly useful for my process and apparatus. In order, however, to avoid deleterious cracking reaction which may be promoted by such catalysts, I prefer to contact my oil with such catalyst adsorbent at a temperature sufliciently elevated to cause a rapid treatment of the oil, but at a temperature suiciently low to prevent deleterious cracking. I also restrict my time of contact in the oontactor to also assist in minimizing deleteri ous cracking reactions.

I have also found for the purpose oi my process, both in order to produce the desirable treating operation and also to permit of the rapid and simple liltration operation made possible by my apparatus, that it is desirable to employ an adsorbent such as mentioned above, for example,

the acid treated sub-bentonites having a close range of particle size, and for this purpose `I have found it useful to employ a material of which about to 100% passes through a 100 mesh and containing less than about 20% to 35% of 0 to 20 micron material.

The mixture of oil and clay thus formed is then agitated and pre-oxidized. The oil is heated by closing switch 55, cap 5 being replaced and the closure 2| being removed. Valve 43 is closed. The cap 3| is in place and the spout 34 is closed, as is valve 39. Valve 35 is opened. Water is passed through coils 33 and 44 and into ejector 45. The ejector creates a vacuum in the condenser 30 and contactor l. Air is drawn through pipes Z4 and 25. It bubbles through the oily and clay in contacter l, agitating them. The air, vapors, and gases discharge through pipe 2l, valve 29, into accumulator'Sii. Any condensible material is collected in 30. Uncondensed gases, vapor and residual air pass through pipe 4B into the ejector 4B.

Since the air discharges into ythe lowermost portion of the mass of oil, a thorough agitation occurs and no sedimentation of the clay is permitted. All portions of the oil are contacted with the clay and subjected to the oxidative influence of the air. As the temperature of the oil rises, the oxidation reaction accelerates. The unstable portion of the oil is adsorbed. The stream of air aided by the vacuum and heat strips the oil of volatile components. Diluent fractions present in the original used oil and any volatile material produced by the pre-oxidation operation are thus removed. The temperature of such pre-oxidation is controlled within the range of about 350 to about 650 F. The thermostat i3 is set to cut out when the temperature rises above the pre determined limit, for instance, 350 to 650 F.

The use of this ejector in the form of a hydroaspirator, employing as the motive power the stream of cooling water passing through the condenser, permits of a ready and simple means of disposing of the highly objectionable odors which Yare present in the uncondensed gases. They are entrained in the stream of water passing from the ejector and are disposed of by passing into the sewer. This permits of the use of the apparatus in an enclosed space where otherwise, due to health hazards and the objectionable odor, expensive provisions must be made for the disposing of such vapors. Especially in inhabited 7 regions, it is not desirable to vent such vapors to the atmosphere, due not only to the pollution oi the air, but also to the nuisance character of such vapors.

The use of an ejector in the manner discussed above is thus superior to the use of a vacuum pump for Which a stack discharge would have to be provided. Some of the advantages of the ejector may be obtained if the discharge of the mechanical vacuum pump is connected to the sewer, and particularly if the discharge of the pump is connected to the water line from 44 so that the vacuum pump discharges are mixed with Water and disposed of by passing to the sewer. The ejectorl and also a vacuum pump have the advantage when employed in the manner described above of drawing air for agitation and for oxidation and of assisting in the removal of volatiles and for purging and agitating with steam. It is also possible but not as advantageous to operate the system at superatmospheric pressure by introducing the steam and air under pressure into the reactor and discharging the air and vapors or gases to the atmosphere through 48. In such case the ejector 45 is omitted and the steam generator is operated under pressure and a valvemay be provided on 24 to disconnect 20 from I and a separate valved connection must be provided to a source of air under pressure to admit air under pressure into I through 24.

As stated above the disposal of the air, vapors, gases, and steam from the line 48 to the sewer, particularly in admixture with the water from 44, is a particularly advantageous procedure, and this advantage of the ejector may in part .be obtained if the discharge from 48, when employing superatmospheric pressures in the chambers I and 30, 4be passed to the sewer, and particularly if the water from 44 be mixed with this discharge and disposed of bypassage to the sewer.

However, the system as described` above employing my ejector is believed simpler and to contain advantages set out above which make it superior to the alternative use of a mechanical vacuum pump and particularly to the use of the agitative air or steam operated under pressure and discharging from the unit at atmospheric pressure.v

When the contact and pre-oxidation operation is complete, usually in about l to 30 minutes, the switch 58 is opened. The water in 29 has been brought to a boil. The cap 2l is placed on the boiler 2|] |and locked in place. Steam pressure is immediately generated in boiler l2i! and steam ows through line 24 and line 25. It bubbles through the oil, keeping the oil agitated and the clay suspended in the oil. Thus there is an immediate substitution of steam for air as an agitating medium and settling of the clay does not occur. The oil and contactor are thus purged of air under the influence of the steam passage aided by the vacuum created by the ejector 46.` Valve 29 is closed and valves 43 and 39 are open. Steam accumulates above the oil level and develops pressure. As soon assuicient pressure is developed, the oil is transferred from the contactor I to the cooler 4I. Cooler 4I is vented through the pipe 40D, cross 40a, valve 3d, into accumulator 3U. The check valve 40 prevents the passage of the vapor stream to the atmosphere. The accumulator is vented through 48 and connected to the ejector 46. Water passing out through the ejector assists in sucking out the vapors, air, and steam.

When all of the oil has been transferred, steam passes through pipe 28, line 31, valve 39, and appears in sight-glass 38. The color in the sightglass changes, indicating the steam is passing through line 31.

The passage of steam through the cooler 4I removes air in the container 4I and thus prevents an oxidation while the oil is at a high temperature. Since, as will be explained more fuliy below, the clay particles settle from the oil, air oxidation at this point while the oil is at a high temperature and in the presence of a diminished quantity of treating agent, resulting from the partial settling of the clay, would re-introduce unstable components into the oil. The use of steam to transfer the hot oil into the cooler and the exclusion of air from contact with the hot oil has also the advantage of preventing flashing of the oil,' particularly when the oil is at above its fla-sh point. This is an important safety factor.

Valve 39 is then closed, valve 43 is closed, and Valve 29 is opened. Steam pressure Will then be vented through contacter I, through valve 21, through line 29, into container 39 to be exhausted through line 48.` The contactor is thus purged of oil vapor. Caps 5 and 2I may then be removed for a new charge of oil to be processed as previously described. rIhe purging of the contacter prevents flashing of the hot oil vapor when the cap 5 is removed.

rIhe oil in container 4I is cooled by cooling coil 44 and a. partial sedimentation of the clay occurs. The oil is cooled to a temperature of below the ash point of the oil, for example, about 300rJ to 400 F. or lower. The pressure in chamber 4I is measured on gauge 49. When the temperature is above 212 F. the pressure will be above atmospheric and therefore no air leaks in through check valve 40. As the temperature drops to below 212 F., the oil is sufficiently re'- sistant to oxidation so that no appreciable harm can be done to the oil by contact with air. Valve 5I] is opened and the oil containing the partially settled clay drops into chamber 5I. A suitable bucket or receptacle is placed under 5I through a door in the closure I9 provided therefor. The clay settles as a pre-coat on the lter 52. An air line is connected to 31 from an air compressor normally available at all garages and service stations. If this is not available, a hand pump may be employed. The oil and clay in 4I are therefore pressured through the filter 5I and when ltration stops the air may then be cut off. Valve 59 is closed and the oil which has been treated in the contacter I during the cooling and ltering operation may be now transferred if sufcient contact time has been provided.

The filter is removed by unscrewing the bolt 56.. The clamp 55 is swung to one side, the perforated disc 54 is removed and a new lter is replaced and assembled by sealing with-clamp and screw 5t and ltration may now be carried out as previously described.

While I have described my apparatus as employing electrical heaters, since theyl are cheap and convenient, they may be replaced by gas or oil burners, particularly when the apparatus is to 'be used where electricity is not available.

As a modication of the above apparatus andas a useful aid in-the proper carrying cut of theprocess, I may provide a convenient package forlinto the chamber so that the filter medium is ad- `jacent the end of the container .5l at theposition occupied )oy-53 in the previous modification. A gasketis provided Vto be placed at the walll 57i and to seal the plate A against the wall. The filter is otherwise assembled as previously described. When the liltration is completed the lter cake will be formed on the iilter medium inside the *container 65 and may be readilydisposedqof by sliding the container from the chamber 5l.

While for economy of construction and simplicity of design numerous automatic devices for opening and closing valves, either on a time cycle or by temperature and pressure controls and the use of indicating or recording devices for the various pressures and temperatures employed, are not employed, they may be introduced. Experience has shown that they are not necessary for the economical and safe execution of my process and for the safe and convenient operation of my device. y

The apparatus and procedures herein described while particularly useful in treating used lubricating oil may also be employed with advantage in treating other lubricating oils as well as vegetable and animal oil or other oils and materials which are susceptible to treatment by means of granular solids, as, for example, adsorb-ents or catalysts.

While I have described a particular embodiment of my invention for the purpose of illustration, it should be understood that various modifircations and adaptations thereof may be made within the spirit of the invention as set forth in the appended claims.

I claim:

1. An apparatus for treating oil,`which com prises a treating chamber, a scalable oil inlet to said chamber, an air and steam inlet to the bottom of said chamber, a vapor outlet from said chamber, a condenser connected to said vapor outlet, a valve in said connection between said treating chamber and said condenser, an oil transfer tube passing through an upper portion of the wall of said treating chamber and extending into and terminating at the lower point of said treating chamber, an oil receiving chamber, a pipe connecting said receiving chamber and said transfer line, a valve in said pipe connection between said oil transfer tube and said oil receiving chamber, a separate air pressure line connected to said reeciver, a vapor outlet from said oil receiving chamber, a connection between said vapor outlet and said condenser, a valve in said lastmentioned connection, a Vacuum generating means connected to said condenser, a liquid discharge line connected to said receiving chamber, and a lter connected to said discharge line.

2. An apparatus for treating oil which comprises a treating chamber, a scalable oil inlet to said chamber, an air and steam inlet to the bottom of said chamber, a vapor outlet from said chamber, a condenser connected tov said vapor outlet, a valve in said connection between said treating chamber and said condenser, an oil transfer tube passing through an upper portion 1f'tl1e`wal1- ofsaid treating chamber and extendinginto and terminating at` the lower point of said treating chamber,` anv oil receiving chamber, a pipe connectingsaid receiving chamber and said vtransfer tube, a coolingv coil in said receiving chamber. a valve in'. said pipe connection between said oiltransfer tube and said oil receiving'chamber, a Yseparate air pressure line connected to said 4receiverja vapor outlet from said oil receiving chamber, a. connection .between said vapor' outvlet'and said condenser, a valve in said last-mentioned: connection, a vacuum generating means `connected to said condenser, a liquid discharge line connected to said receiving chamber, and a iilter connected` to said discharge line.

3. An apparatus for treating oil, which comprises a treating chamber, a `scalable oil inlet to said chambenran air and steam -inlet to the bottom of said chamber, a vapor outlet from said chamber, a condenser, a cooling coil in said condenser, a vapor line connected to said vapor outlet and to said condenser, a valve in said connection between said treating chamber and said condenser, an oi1 transfer' tube passing through an upper portion of the wall of said treating chamber and extending into and terminating at the lower point of said treating chamber, an oil receiving chamber, a pipe connecting said receiving chamber and said transfer tube, a cooling coil in said receiving chamber, a valve in said connection between said oil transfer line and said receiving chamber, a separate air pressure line connected to said receiver, a vapor outlet from said oil receiving chamber, a connection between said vapor outlet and said condenser, a valve in said last-mentioned connection, a water jet connected to said condenser, a water connection between said cooling coils and said water jet, a liquid discharge iline to said receiving chamber, and a lter connected to said discharge line.

4. An apparatus for treating oil, which comprises a treating chamber, a scalable oil inlet to said chamber, an air and steam inlet to the bottom of said chamber, a vapor outlet from said chamber, a condenser connected to said vapor outlet, a, valve in said connection between said treating chamber and said condenser, an oil transfer tube passing through an upper portion of the wall of said treating chamber and extending into and terminating at the lower point of said treating chamber, an oil receiving chamber, a pipe connecting said receiving chamber and said transfer tube, a valve in said pipe connection between said oil transfer tube and said oil receiving chamber, a separate air pressure line connected to said receiver, a vapor outlet from said oil receiving chamber, a connection between said vapor outlet and said condenser, a sight glass in said pipe, a valve in said last-mentioned connection, a vacuum generating means connected to said condenser, a liquid discharge line to said receiving chamber, and a iilter connected to said discharge line.

5. An apparatus for treating oil, which comprises 'a treating chamber, a scalable oil inlet to said chamber, an air and steam inlet to the bottom of said chamber, a vapor outlet from said chamber, a condenser, a cooling coil in said condenser, a pipe connected to said vapor outlet and .oil transfer tube and said receiving chamber, a

separate air pressure line connected to said receiver; a vapor outlet from said oil receiving chamber, a connection between said vapor outlet and said condenser, a sight glass in said pipe,

a valve in said last-mentioned connection, a wa- Y ter jet connected to said condenser, a water connection between said cooling coils and said water jet, a liquid discharge line to said receiving chamber, and a lter connected to said discharge line.

MYRAN J. LIVD'GSTON.

REFERENCES CITED The following references are ofrecord in the file of this patent:

Number UNITED STATES PATENTS Name Date Miller June 16, 1942 Harris May 18, 1943 Moreton Nov. 17, 1931 Miller Nov. 24, 1936 Harris May 18, 1943 Moreton Nov. 17, 1931 Belden Sept. 15, 1931 Palmer Dec. 28, 1937 Boyce Apr. 4, 1944 Behmer Mar. 21, 1933 Gerin Apr. 4, 1944 Ireland Apr.l 5, 1932 FOREIGN PATENTS Country Date Number French Mar. 18, 1935 

